Electron Mobility Enhancement of Extremely Thin Body In$_{0.7}$Ga$_{0.3}$As-on-Insulator Metal–Oxide–Semiconductor Field-Effect Transistors on Si Substrates by Metal–Oxide–Semiconductor Interface Buffer Layers

Abstract

The electron mobility enhancement of extremely thin body In0.7Ga0.3As-on-insulator (-OI) metal–oxide–semiconductor field-effect transistors (MOSFETs) on Si substrates by using In0.3Ga0.7As MOS interface buffer layers was demonstrated. The MOSFETs with the InGaAs thickness of 2/5/3 nm have exhibited the electron mobility of 2810 cm2 V-1 s-1 with an enhancement factor of 4.2 against that of Si MOSFET. We have examined the body thickness (Tbody) dependence of the electron mobility. It was found that a channel thickness fluctuation scattering mechanism strongly affects the mobility in Tbody of around 10 nm and thinner. The formation of a uniform and flat InGaAs-OI wafer is required for further improvements.